Search results for "Exchange"
showing 10 items of 2035 documents
On the modelling of an Acid/Base Flow Battery: An innovative electrical energy storage device based on pH and salinity gradients
2020
Abstract Electrical energy storage can enhance the efficiency in the use of fluctuating renewable sources, e.g. solar and wind energy. The Acid/Base Flow Battery is an innovative and sustainable process to store electrical energy in the form of pH and salinity gradients via electrodialytic reversible techniques. Two electromembrane processes are involved: Bipolar Membrane Electrodialysis during the charge phase and its opposite, Bipolar Membrane Reverse Electrodialysis, during the discharge phase. For the first time, the present work aims at predicting the performance of this energy storage device via the development of a dynamic mathematical model based on a multi-scale approach with distr…
A steady state and dynamic fuel cell model including temperature effects
2009
In the last few years fuel cells have attracted much interest from both academic and industrial researchers to replace current lithium-ion and similar rechargeable battery systems. A wide variety of research areas benefit from fuel cell use: electro-chemical, stationary, transportation and portable electronics can be cited as an example. Potential applications range from few watts to megawatts systems. Even concerning quite different scientific areas, fuel cell modelling is a common requirement. The complexity of such a topic relies not only on the modelling approach but also in the model structure and implementation. In this paper a steady state and dynamic fuel cell circuital model includ…
Social capital development of rural community based on social networking activities in Lithuania
2018
The scholar literature on simultaneous using of social capital explore knowledge and identity resources as well as actions and interactions benefiting the community through personal bonds of individuals; issues of common trust; and adapting the current understanding in new situations. In this article, we instead examine rural community influence on social capital building of adult person in a virtual community. A quantitative survey was done in 246 local rural communities in Lithuania which reflected their community activities on a virtual basis. From the data of 500 informants we found that rural community (human social network) members were also active in the virtual communities. Research…
Counter-complementarity control of the weak exchange interaction in a bent {Ni(ii)3 complex with a μ-phenoxide-μ-carboxylate double bridge
2019
We have prepared and structurally characterized a novel {Ni3} bent complex bearing a double μ-phenoxide-μ-carboxylate bridge. Both terminal Ni(ii) sites are symmetry related, offering a simplified exchange interaction scheme. DC magnetic data is consistent with a weak antiferromagnetic interaction between the central and terminal Ni(ii) ions. As expected for a Ni(ii) system, local zero-field splitting is observed, which can be experimentally established. Broken symmetry quantum chemical calculations, as well as ab initio CASSCF-SA-SOC computations that support the magnetic experimental data, were also performed. From the analysis of other reported closely related Ni(ii) systems, a counter-c…
Clusters and Industrial Districts: Where is the Literature Going? Identifying Emerging Sub-Fields of Research
2015
[EN] The industrial district and cluster literature has generated an extraordinary quantity of articles, debates and topics for discussion, and encompasses one of the most vibrant lines of research in the field of economics, geography, management and related disciplines. The literature, however, is fairly fragmented. In this paper, “bibliometric” methods are used to analyse the cluster literature published between 1957 and 2014 in order to explore “prospective” research priorities through the method of “bibliographic coupling”. Beyond focusing on foundational works in the past, this approach shifts the focus away from the practice of analysing co-citations and seminal contributions to one o…
Promoting Deoxygenation of Bio-Oil by Metal-Loaded Hierarchical ZSM-5 Zeolites
2016
3 Figuras.- 5 tablas.-1 Esquema.- This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Sustainable Chemistry & Engineering, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acssuschemeng.5b01606 ”
Separation and purification of no-carrier-added arsenic from bulk amounts of germanium for use in radiopharmaceutical labelling
2010
AbstractRadioarsenic labelled radiopharmaceuticals could add special features to molecular imaging with positron emission tomography (PET). For example the long physical half-lives of72As (T1/2=26 h) and74As (T1/2=17.8 d) in conjunction with their high positron branching rates of 88% and 29%, respectively, allow the investigation of slow physiological or metabolical processes, like the enrichment and biodistribution of monoclonal antibodies in tumour tissue or the characterization of stem cell trafficking. A method for separation and purification of no-carrier-added (nca) arsenic from irradiated metallic germanium targets based on distillation and anion exchange is developed. It finally con…
Determination of biogenic amines in meat by combined ion-exchange capillary gas chromatography
1984
Abstract A procedure is described for the determination of putrescine, cadaverine and histamine in meat. Crude perchloric acid extracts were pre-separated on a weakly acidic cation exchanger and the amines quantified by capillary gas chromatography. The diamines were analysed as trifluoroacetyl derivatives and histamine was converted into N α -trifluoroacetyl-N τ -ethoxycarbonylhistamine. The accuracy of the determination of diamines was examined by a precipitation pre-separation method and by mass fragmentometric quantification. The proposed procedure allows the sensitive, sufficiently precise and highly specific determination of putrescine and cadaverine in meat.
Regulatory factor for the transcription of the ribosomal genes in amphibian oocytes.
1970
AMPHIBIAN oocytes provide very convenient material for the study of the mechanisms that control ribosomal RNA synthesis because their pattern of ribosomal RNA synthesis does not change greatly during oogenesis. During the lampbrush stage of oogenesis (stage 4) more than 97 per cent of the RNA synthesized per unit time in the oocytes is ribosomal. This happens because the genes for ribosomal RNA are specifically amplified3–5 to such an extent that the oocyte nucleus (germinal vesicle) has an rDNA content approximately 1,500 times more than the haploid amount4. On the other hand, in mature oocytes (stage 6) no ribosomal RNA is synthesized1,2, although the extra copies of the ribosomal cistron…